A point on the rim of a 0.30-m-radius rotating wheel has a tangential speed of 5.0 m/s.What is the tangential speed of a point 0.20 m from the center of the same wheel?
A)1.0 m/s
B)0.50 m/s
C)3.3 m/s
D)17 m/s

Question

Quizplus · Accepted Answer

The tangential speed of a rotating object can be found using the formula v = rω, where v is the tangential speed, r is the radius of rotation, and ω is the angular velocity of the object. Since the two points on this wheel are rotating at the same angular velocity (since they are part of the same rigid object), we can set their tangential speeds equal to each other:

v1 = r1ω
v2 = r2ω

where v1 is the known tangential speed (5.0 m/s), r1 is the known radius (0.30 m), and r2 is the unknown radius (0.20 m). We can then solve for v2:

v2 = (r2/r1) v1 = (0.20 m / 0.30 m) (5.0 m/s) ≈ 3.3 m/s

Therefore, the answer is C.

A Point on the Rim of a 0